During construction of a wall it is desirable to mount an electrical junction box in a manner so that the electrical junction box does not move or shift during construction of the wall and during use after completion of the structure. Numerous mounting devices have been proposed for permanently and/or temporarily mounting electrical boxes in the cavity of a wall during construction.
The standard outlet boxes often require mechanical fasteners to secure the electrical box permanently in place to a wall stud or other support structure. The mechanical fasteners are usually positioned to orient the electrical box in the desired location so that the outer edge of the electrical box is flush with the outer face of the wall.
The mounting of electrical boxes in concrete structures generally requires a different mounting assembly for holding the electrical box in position while the wall is being formed. In addition, concrete wall and building block walls do not enable the usual fasteners that are used in wood walls and studs since nail, screws and other fasteners cannot be easily driven into the wall. Electrical boxes are required to be secured to the wall to prevent movement of the box after installation. Hollow concrete blocks provide a particular difficulty in mounting electrical boxes since there are no surfaces that can readily accommodate fasteners.
Various methods have been proposed for mounting or supporting electrical boxes during construction of the concrete walls and block walls. One manner of mounting the electrical box is to provide a sheet metal form with various tabs that can hold the electrical box in position while the cement or mortar sets. These devices often require the device to be positioned between the joints during the construction of the wall which can interfere with the structural integrity of the joint. These devices also require the use of cement or mortar to hold the support in place.
Various devices and methods have been proposed for mounting an electrical box during construction. One example is disclosed in U.S. Pat. No. 2,581,755 to Dieffenderfer which discloses an electrical connection box having a bracket member for mounting to the outer sides of the walls of the box. The brackets are folded to form an outwardly projecting flange and overlap the front side of the wall. Slots are provided for receiving mounting screws to attach the bracket to the box. The bracket has inwardly projecting bendable arms with weakened zones and straps integral with the arms that are folded in a reverse direction. The electrical box and the brackets are inserted into the opening in the wall and the straps are folded outwardly causing the arms to bend and contact the inner surface of the wall.
U.S. Pat. No. 2,736,450 to Atkinson discloses an outlet box securing device. The securing device has a hook portion for contacting the outer edge of the electrical box, a flat portion extending from the hook portion and a spring arm forming a U-shaped loop. The spring arm has one end that contacts the inside surface of the opening to apply a spring force between the side edge of the opening in the wall and the electrical box.
U.S. Pat. No. 3,184,191 to Esoldi discloses an electrical box holder having legs formed in a U-shaped for engaging the open end of the electrical box. The center leg of the holder is pulled outwardly with respect to the electrical box causing the body of the holder to bend 90° and contact the inner surface of the wall. The center leg is then folded over the edge of the electrical box.
U.S. Pat. No. 3,337,168 to Albrecht discloses an electrical box support having a pair of outwardly extending legs that are inserted through the opening in the wall to contact the inner surface of the wall. Tabs are then folded over the front edge of the electrical box to secure the electrical box in place.
U.S. Pat. No. 3,362,667 to Ginsberg discloses an electrical switch box support having an outer wall for contacting the outer surface of the wall and an inner wall contacting the inner surface of the wall and forming a channel therebetween. The body of the support includes tabs that are bent over the open edge of the electrical box to attach the electrical box to the support.
U.S. Pat. No. 4,183,486 to Esoldi discloses an electrical box holder that is inserted into the opening in the wall between the edges of the opening in the side wall of the electrical box. The holder includes a bendable and collapsible center portion and leg extensions on each side of the center portion. The leg extensions extend beyond the front face of the electrical box and the wall and are pulled outwardly causing the center portion to bend and engage the inner surface of the wall.
U.S. Pat. No. 4,693,438 to Angell discloses an electrical box retainer having a U-shaped clip like member having an outwardly extending spring biased flange. The spring biased flange is inserted between the outer edge of the electrical box and the opening in the wall to contact the inner surface of the wall. The main body of the clip is bent over the inner edge of the electrical box.
U.S. Pat. No. 4,669,371 to Sarazen et al. discloses a mounting spring for a foundation vent. The spring clips to the front edge of the vent and has a pair of spring biased legs to contact the inner edge of the opening in the wall.
U.S. Pat. No. 5,494,244 to Walton discloses a similar mounting clip for an air diffuser. The mounting clip has a U-shaped portion that slides onto the inner edge of the opening in the wall and an inwardly extending leg to contact the outer surface of the vent.
U.S. Pat. No. 5,661,264 to Reiker discloses an electrical box having a U-shaped mounting bracket is attached to the rear wall of the electrical box. The mounting bracket has outwardly extending legs for supporting the electrical box.
U.S. Pat. No. 6,648,277 to De Leu discloses an electrical box mounting strap for supporting an electrical box within a cavity of the concrete block. The mounting strap has a configuration to conform to the surface of the cavity of the block and has a leg portion to support the rear and side walls of the electrical box to prevent the electrical box from moving inwardly into the cavity of the concrete block.
U.S. Pat. No. 7,455,266 to Faircloth discloses an electrical conduit support for use in concrete block. The support has a main body portion with a plurality of openings for receiving the conduits and outwardly extending tabs or flanges that contact the upper surface of the concrete block and is captured between the adjacent concrete blocks.
U.S. Pat. No. 8,109,054 to Thomas et al. discloses a fastener for an electrical box within a concrete block. The fastener has a front portion, a center portion and an end portion. The end portion and the center portion of the fastener are inserted through the utility box with part of the end portion extending beyond the back surface of the utility box. The front portion rests across the front surface of the utility box. The end portion is secured against the back surface of the utility box to maintain the position of the utility box within the wall.
While the prior devices are generally suitable for their intended purpose there is a continuing need in the industry for improved methods and devices for mounting electrical boxes during construction of concrete and block walls.